Let’s build this Peanut Butter Chocolate masterpiece, emphasizing the finishing techniques:

1. Bake and Cool Cake Layers:

Preheat oven to 350°F (176°C). Prep three 8-inch pans (grease, parchment, spray). Make the chocolate cake batter following the recipe’s simple wet-into-dry, then hot liquid method. Ensure ingredients are well combined but don’t overmix after adding water. Divide batter evenly (use a scale for precision!). Bake 22-25 minutes until a toothpick has moist crumbs. Cool 2-3 mins in pans, then invert onto racks, remove parchment, cool completely. Completely cooled cakes are essential for frosting.

2. Make Peanut Butter Frosting:

In a large mixer bowl (paddle attachment), beat room temperature salted butter and peanut butter until well combined and smooth. Gradually add about half the sifted powdered sugar, mixing on low until incorporated, then medium until smooth. Add 3 tbsp water/milk, mix until smooth. Add remaining sifted powdered sugar, mix on low then medium until smooth. Add remaining 3-4 tbsp water/milk, 1 tbsp at a time, until frosting is smooth and spreadable but still holds shape. Beat well after final liquid addition until light and fluffy.

3. Level and Fill the Cake:

Once cakes are completely cool, use a long serrated knife to level the tops flat. A turntable helps get an even cut. Place the first cake layer on a serving plate or cardboard cake circle on your turntable. Top with about 1 cup of frosting. Using an offset spatula, spread it into an even layer. Sprinkle about half (3 chopped Reese’s) over the frosting. Gently press them in. Spread a very thin layer of frosting over the Reese’s (just enough to act as glue for the next layer). Add the second cake layer. Repeat frosting, chopped Reese’s, and thin “glue” frosting layer. Add the final cake layer, placing it upside down for a perfectly flat top surface.

4. Apply the Crumb Coat:

Using an offset spatula, apply a thin layer of peanut butter frosting over the entire cake (top and sides). Focus on filling any gaps between layers and trapping all loose crumbs. It doesn’t need to look pretty! Use a bench scraper held vertically against the sides while rotating the turntable to smooth the crumb coat slightly. Chill the cake for at least 30 minutes until the frosting is firm to the touch.

5. Apply the Final Frosting Coat:

Apply the remaining peanut butter frosting generously over the top and sides of the chilled cake. Using a large offset spatula, smooth the top. Using a bench scraper held vertically against the side at a 45-degree angle to the direction of rotation, rotate the turntable smoothly to create smooth sides. Remove excess frosting from the scraper frequently. Repeat until sides are smooth. (Optional Stripes as per original video reference: After smoothing, gently press the tip/edge of a small offset spatula into the frosting at the base and rotate the turntable to create horizontal lines, moving upwards slightly with each rotation). (Optional Viva Towel method referenced: For ultra-smooth American buttercream, chill the frosted cake until very firm, then gently lay a non-patterned Viva paper towel over the frosting and smooth over it lightly with a fondant smoother or your hand. This recipe omits this step due to the stripes/drip).

6. Make and Apply Ganache Drip:

Put chocolate chips in a heatproof bowl. Microwave heavy cream until just boiling. Pour hot cream over chips. Let sit 2-3 minutes. Whisk gently until completely smooth. Let ganache cool slightly until it’s thickened to a good drip consistency (test on a cold plate – it should drip slowly but not run too fast). Using a squeeze bottle or spoon, apply drips around the top edge of the chilled, frosted cake. Work quickly but carefully. Pour remaining slightly cooled ganache onto the center top of the cake. Gently spread it to meet the drips using a small offset spatula.

7. Final Decorations:

Allow the ganache to set slightly (about 10 minutes at room temp or briefly in fridge). Transfer some reserved peanut butter frosting (or make extra/use leftover vanilla dam frosting) into a piping bag fitted with a large closed star tip (Ateco 844, Wilton 2D or 1M). Pipe decorative swirls or rosettes around the top edge of the cake, on top of the ganache. Top the swirls with Reese’s Peanut Butter Cups cut in half. Sprinkle Reese’s crumbles in the center or around the base.

8. Chill and Serve:

Refrigerate the cake until ready to serve (at least 30 mins for ganache/frosting to fully set). For best flavor and texture, let the cake sit at room temperature for about 20-30 minutes before slicing. Use a tall, sharp knife dipped in hot water and wiped clean between cuts. Store leftovers covered in the refrigerator.